In the electronics industry, there is a constant demand for electronic devices, such as integrated circuits (ICs) or semiconductor chips, to be produced less expensively and in smaller dimensions. One way to reduce the unit cost of such electronic devices is to increase the test speed of the devices by testing a plurality of them at the same time.
It has become a test technology standard to place a number of electronic devices to be tested on a test tray and position them so as to be engaged by a test head plate having a number of corresponding test contractors. On the test tray, a number of IC carriers are positioned by column and row. A handler (i.e., a handling device) withdraws electronic devices from a stack or magazine and places one device on an IC seat or in an IC pocket of each IC carrier. The test tray, having a number of such IC carriers, is then arranged so as to be in vertical alignment (either above or below) with a test fixture.
Such test trays have been described, for example, in U.S. Pat. No. 5,675,957 (Kim), U.S. Pat. No. 5,909,657 (Onishi et al.) and U.S. Pat. No. 6,856,128 (Ito et al.). Each of these patent references is incorporated herein by reference.
The test tray comprises a rectangular frame having one or more equally spaced apart parallel cleats between the opposed major side frame members of the frame, and a multiplicity of IC carriers mounted between each pair of opposed cleats and between each of the side frame members and the opposed cleats.
The exterior shape of the test tray is adapted for use with a certain type of handler, i.e., it is handler specific, whereas the shape and size of the IC carriers are adapted for use with a certain type of electronic devices, i.e., the IC carriers and their arrangement on the test tray are device specific. Therefore, it is necessary for the manufacturer of such electronic devices to have one specific tool for every combination of handlers and device types. This leads to great expenditures for such tools and increases the cost of production.
Thus, there is a need for a test tray with IC carriers (hereinafter called “handling unit”) that can overcome the problems and disadvantages described above.